Bearings are generally used to support and hold a rotating member attached to a non-rotating member. This can be e.g. a wheel on a vehicle, a vane on a wind turbine or a drum in a washing machine. During use, the bearing is subjected to different loads, both static and dynamic. The static load is mainly due to the weight of the machine, while the dynamic loads are due to the working conditions of the machine. A bearing comprises an outer ring with an outer raceway, an inner ring with an inner raceway and rolling elements.
Some bearings are provided with a flange, either on the outer ring or on the inner ring. The flange may be used to aid the positioning of the bearing, or may be used for mounting the bearing.
A flange is normally machined together with the bearing ring. This is not a problem for small bearings, but for larger bearings, with a diameter of more than 0.5 meters, such a traditional method of machining a flanged bearing ring is very expensive. Machine and tool cost are high, and the cost due to the time needed to remove all excess material is also very high, since the bearing is machined form a single piece of metal. Further, the material waste is huge, which is also a drawback when it comes to cost and to a sustainability perspective.
It is known to join a separate flange to a bearing ring. The bearing ring is machined separately and may be provided with some adaptations, such as grooves or protrusions, which will make the joining easier. The flange is machined as a separate part and is joined to the bearing ring by welding. It is however difficult to achieve the required mechanical properties for a welded bearing ring joint. The welded joint region will have different mechanical characteristics, which will constitute a weakening. Such a bearing must thus be dimensioned accordingly, which means that the bearing will be larger and heavier than a non-welded bearing adapted for the same load.
There is thus room for an improved flanged bearing ring and for a method for producing such a flanged bearing ring.